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Characterization of modern HPLC columns and their application potential
Janečková, Lucie ; Tesařová, Eva (advisor) ; Pacáková, Věra (referee) ; Flieger, Miroslav (referee)
(EN) The aim of the dissertation thesis is characterization of modern HPLC columns from the point of their interaction possibilities and demonstration of their application potential. The first part of the thesis is focused on alternative reversed-phase HPLC columns based on zirconium dioxide. These packings offer excellent chemical stability and additional interactions that can be helpful in the development of analytical methods. A detailed study of the chromatographic behaviour of biologically active nonapeptides as model analytes confirmed the substantial effect of mobile phase composition on retention mechanism. Consequently, HPLC separation systems with zirconia-based polystyrene column were characterized by distinct approaches that allowed recognition of the interactions participating in the separation process. Empirically based chromatographic tests evaluated the fundamental properties of the system - hydrophobicity and polarity. The complex model of linear free energy relationship described the prevailing interactions in different separation systems. Application of a set of basic compounds revealed the contribution of ion-exchange interactions participating in the separation systems with zirconia-based column. The second part of the thesis is devoted to new cyclofructan-based chiral...
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Determination of aminoglutethimide using HPLC-ED on carbon pastes
Vlachová, Karolína ; Šestáková, Ivana (referee) ; Zima, Jiří (advisor)
In this thesis, the determination of AGT, sooner used as anticancer drug, especially for the treatment of breast cancer in postmenopausal women or for the treatment of prostate cancer, by high performance liquid chromatogramy with UV spectrophotometric detection (HPLC-UV) and electrochemical detection (HPLC-ED) on carbon paste electrodes (CPEs) was studied. CPEs were prepared from glassy carbon microspheres and different pasting liquids - routinely used mineral oil (CPE-MO) and less commonly used tricresylphosphate (CPE-TCP) and silicone oil (CPE-SO). The concentration dependences of AGT were measured by HPLC-UV with detection wavelength 242 nm, by HPLC-ED with a working potencial of +1,3 V for CPE-MO and + 1,1 V for CPE-TCP in mobile phase containing phosphate buffer (pH 4) and methanol 50:50 (v/v). The following limits of detection were achieved - 3,6. 10-7 mol.l-1 for UV spectrophotometric detection, 2,5. 10-7 mol.l-1 for electrochemical detection with CPE-MO and 9,7. 10-7 mol.l-1 for electrochemical detection with CPE-TCP. AGT was also determined in model samples of urine. With HPLC-UV it was not possible to detect AGT, because of the interferences of other compounds. With HPLC-ED on CPE-MO the limit of detection 5,2. 10-7 mol.l-1 AGT was achieved. KEY WORDS Aminoglutethimide HPLC with UV...
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In vitro cultures of medicinal of plants - X
Maliňáková, Lenka ; Tůmová, Lenka (advisor) ; Kašparová, Marie (referee)
In vitro cultures of medicinal plants - X Aim of this study was to study the effect of abiotic elicitation on production of rutin in callus and suspension culture of Fagopyrum esculentum Moench. Cerium chloride (CeCl3) was used as elicitor at three different levels of concentration. The content of rutin in cell cultures was determined by HPLC. Cell cultures were cultivated on Murashige - Skoog medium with the addition of 10 mg/ml of 2,4-D as a growth regulator. No rutin was produced in both types of culture without the presence of elicitor. The maximal content of rutin in callus culture was determined after 6 hours of treatment with elicitor solution with concentration c1 (4,057.10-3 mol/l.). No production of rutin was observed in suspension culture.
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Silybum marianum in vitro-abiotic elicitation.
Adamová, Eva ; Tůmová, Lenka (advisor) ; Martin, Jan (referee)
Elicitation is the method to increase the production of secondary metabolites in plant tissue. Elicitation by electric field is one of the method of abiotic elicitation to stimulate plants to produce higher amount of secondary metabolites. In vitro cultures of Silybum marianum were cultivated on Murashige-Skoog medium. Suspension cultures were exposed to electric field (50 mA, voltage 5, 7, 8, 10, 15, 20, 24 V) during 10, 30 and 60 minutes. The content of silymarin complex components was measured by (HPLC). The maximal content of taxifolin (0.04 %), silychristin (0.28 %), silydianin (0.06 %) in suspension culture was detected after elicitation by electric field 8V (10 minutes, 6 hours). The maximal content of taxifolin, silychristin, silydianin in suspension culture was detected after elicitation by electric field 8V (60 minutes, 6 hours) and 10V (60 minutes, 24 hours). The significant increase of silymarin complex components were not detectable after the other values of voltage .
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Use of some exotic natural extracts in cosmetics
Phan, Huong Tra ; Němcová, Andrea (referee) ; Márová, Ivana (advisor)
The objective of this bachelor thesis was a general characterization of the antioxidant effect of exotic plants and their extracts. The selected plants were Zingiber officinale, Turmeric longa and Momordica charantia. Theoretical part focuses on antioxidative properties, genereal characteristics of selected plants and description of the methods applied in the experimental part. In the experimental part, content of the antioxidant activity, polyphenols, flavonoids were characterized by spectrophotometry. Major active ingredient (curcumin, gingerol) and other substances like tocopherol were determined by HPLC/UV-VIS. Finally, potential practical use of these active substances in the field of cosmetics including skin hydration measurement was tested.
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Effect of vitamin E on oxidative stress and the basement membrane in lungs in vitamin A-defficient rats
Fabšíková, Katarína ; Wsól, Vladimír (advisor) ; Zemanová, Lucie (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Katarína Fabšíková Supervisor: Prof. Ing. Vladimír Wsól, Ph.D. Title of diploma thesis: Effect of vitamin E on oxidative stress and the basement membrane in lungs in vitamin A-deficient rats In the experiment described in this thesis there was being observed the effect of long-term deficiency of vitamin A on the basement membrane in rat lungs. Rats were divided during the experiment into several groups differing in composition of feed and the changes of pulmonary basement membrane were being observed. Consequently, the effect of vitamin E and retinoic acid on membrane modifications was watched, too. During the experiment there was evaluated the rate of oxidative stress by the medium of glutathione and malondialdehyde levels, which act as its markers. These levels in all experimental animals were specified by HPLC chromatography. Also, the oxidative stress was assessed using other markers such as thickness of the basement membrane, deposits of collagen fibers and levels of retinol and α-tocopherol in plasma and tissues. This experiment should confirm the important role of vitamins acting as antioxidants in prevention and treatment of pathological changes caused by increased oxidative...
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Content of rutin in the biological waste material from plantations of elderberry
Boháčová, Hana ; Vránová, Dana (referee) ; Vespalcová, Milena (advisor)
This thesis is focused on determining the concentration of rutin in twigs elderberry (Sambucus nigra L.). The theoretical part provides an overview of the properties, occurrence and use of elderberry in folk medicine, medicine and food. Furthermore, there are the most important substances contained in elderberry, especially flavonoids, including rutin and quercetin as well. There are briefly described their properties, biological effects and possibilities of determination. The content of the experimental part of the thesis was developed cheap extraction methods to obtain the maximum yield of dried twigs rutin elderberry. Rutin content was observed in twigs cultivated elder varieties and wild elderberry. The identification and quantification of rutin in extracts was optimized and validated method of high performance liquid chromatography (HPLC). As a comparative method to develop extraction was used a pressurized hot water extraction (PHWE). There were tested three particle sizes of shredded twigs. The particles were extracted differently hot water varying duration. Most rutin was found in samples milled at 4 mm particles. The optimum time and temperature of extraction was 7 hours at 80°C. The highest amount of rutin in bred elderberry was determined in a sample Mladší 2014, digestion using 1,49 ± 0,004 mg.100g-1 and method PHWE 5,75 ± 0,015 mg.100g-1. There was determined the most rutin in a sample Září 2014 in the wild variant of elderberry. By digestion of ground twigs was obtained 0,90 ± 0,022 mg.100g-1 of rutin, using PHWE 2,98 ± 0,022 mg.100g-1.
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In vitro cultures of medicinal plants - XI.
Sojková, Kristýna ; Tůmová, Lenka (advisor) ; Kašparová, Marie (referee)
In vitro cultures of medicinal plants - XI. Elicitation is one of the few strategies that can be used in enhancement of secondary metabolites production from explant cultures. The effect of abiotic elicitor (silver nitrate) on flavonolignan and flavonoid taxifolin production in suspension culture of Silybum marianum L. (Gaertn.) and on isoflavones production in suspension culture of Genista tinctoria L. was tested. Silver nitrate in various concentrations (5.887.10-3 mol/l; 5.887.10-4 mol/l; 5.887.10-5 mol/l) was used as elicitor. Content of secondary metabolites in suspension cultures was determinated by high performance liquid chromatography (HPLC). The samples were taken after 6, 12, 24, 48, 72 and 168 hours after elicitor treatment. The highest content of taxifolin production (0.02 %) in suspension culture of Silybum marianum L. (Gaertn.) after silver nitrate (5.887.10-4 mol/l) treatment and 72 h sampling was detected. The highest content of genistin (0.05 %) in suspension culture of Genista tinctoria L. was found after silver nitrate (5.887.10-4 mol/l) treatment and 48 h sampling. The highest content of daidzein (0.09 %) was detected after elicitor (5.887.10-4 mol/l) treatment and 168 h sampling.
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Comparison of qualitative indicators varieties of hops (Humulus lupulus) from various types of hop fields
KORCOVÁ, Žaneta
The aim of this thesis was to determine content of - a -bitter acids in samples of hop obtained from different types of growing regions. Object of research were cultivars of Saaz late, Sládek and Premiant cultivated in three growing regions (Žatecko, Úštěcko, Tršicko) in year 2015. Nine hop samples from conventional agriculture and one from bio production were examined. For all growing areas, from which hop cones were obtained, was determined altitude, rainfall and average temperatures during vegetation period. Quantity of bitter acids were measured by HPLC. Our calculated correlation coefficients showed that the higher altitude and average temperature the lower content of bitter acids was measured and more precipitation has positive impact on content of bitter acids.
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Determination of selected chemical parameters of fruit of new currant varieties
Pelikánová, Blanka ; Diviš, Pavel (referee) ; Vespalcová, Milena (advisor)
Presented diploma thesis is dedicated to the determination of selected chemical parameters of fruits of new currant varieties. The theoretical part is focused on the characteristics of currant, the biologically active substances of its fruits and also the utilization of current in the food industry. Further part of the theory deals with the main chemical parameters which were examined: polyphenols, anthocyanins, ascorbic acid and antioxidant activity. In the practical part there were determined selected chemical parameters in six white, twelve red and thirteen black varieties of currant. Anthocyanins and polyphenols have been determined spectrophotometrically. The content of ascorbic acid in selected varieties of currant was determined by HPLC. As a technique for the determinationof the antioxidant activity was selected the method of free radical DPPH.
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